Dexter (Michael C. Hall), right, and Deb (Jennifer Carpenter) were on the outs as the final season got under way. / Randy Tepper, Showtime

by Bill Keveney, USA TODAY

by Bill Keveney, USA TODAY

SAN DIEGO -- Comic-Con fans showed their love for a serial killer Thursday as longtime favorite Dexter made its final appearance at the fan convention.

The Showtime drama with one of TV's most unusual protagonists finished shooting its final season last week and the finale will run in September.

The panel was mostly laughs, but there were a few tears, as actors discussed the impending end.

Michael C. Hall, who plays Dexter Morgan, a blood-spatter expert with a gruesome sideline, said the ending will sink in about when it would have been time to return to shoot a new season.

"Our conscious minds are aware that it's over. Our bodies, five months from now, will start knocking on the door, wondering why we're not doing Dexter again," he said.

Clyde Phillips, who ran the show's production in its early seasons, recalled Dexter's growth in prominence at Comic-Con, where it occupied the convention center's biggest room Thursday. "The first time we were in this little room. Now, we're in the room that Iron Man gets."

The large panel featured actors whose characters had died during the show's run, including Julie Benz, Erik King and Lauren Velez. John Lithgow, who did a famed turn as The Trinity Killer, paid tribute via taped video.

"I wish I could be with you today but, as you know, I'm dead," he said, referring to his character's demise.

Hall said he took a number of mementos from the set, including Dexter's watch, his lanyard with his I.D. and a nine-foot piece of railing outside Dexter's apartment that he plans to put his his backyard.

He wanted to pick up some blood-spatter images in Dexter's laboratory, but someone grabbed them before him. Co-star Jennifer Carpenter's body language suggested she was the culprit, but she wouldn't confess to specifics.

"I took a lot," she said gleefully. "It was fun."

When Hall was asked what he does to get into character, he answered a different question, one that may have more resonance as the role fades into the past.

"I think I need to focus on some rituals to get out of character," he said.

With time left for more mayhem as the finale approaches, Hall recalled how his previous series ended its run.

"At the end of Six Feet Under, we all get to die," he said. "That was nice."